Window treatments are well known. In addition to aesthetic features, window treatments also provide privacy, protection from excessive sunlight, and thermal insulation. Certain previously developed window treatments include dual shade panels made of a fabric or other flexible material, whereby the dual shade panels can alternatively be wound onto and deployed from a single spool, and once deployed, the dual panels hang adjacent one another and may be shifted vertically relative to one another to adjust the amount of sunlight passing through the shade panels. Examples of such vertically shiftable window treatments are disclosed in U.S. Pat. Nos. 58,668; 2,280,358; 6,189,592 and applicants' U.S. Pat. No. 6,651,720.
There is a need in the window treatment art for a combination dual panel, roll up shade apparatus where the panels are vertically deployed and rolled up, and one or both of the panels are also capable of shifting horizontally in relation to each other to very the amount of light passing through the shade panels.
There is also a need for the combination window shade apparatus having a single control mechanism that allows a user to vertically deploy and roll up the shade panels, and to shift the shade panels horizontally.